Definition: Planar Graph
Let \(G(V,E,\gamma)\) be an undirected graph \(G\) is called planar, if there exists a planar drawing for this graph.
Notes
 Please note that planarity and not a property dependent on whether the graph has loops or multiedges.
 Also, it does not matter if the edges are directed or undirected.
 Thus, for convenience reasons, we may restrict our attention to simple undirected graphs only, when we study planar graphs.
Example:
A planar graph (left) with its planar embedding (right):
A graph, which is not planar:
Mentioned in:
Chapters: 1 2
Corollaries: 3 4
Definitions: 5 6
Explanations: 7
Lemmas: 8 9
Persons: 10
Problems: 11 12
Proofs: 13 14 15 16 17 18 19 20 21 22
Propositions: 23 24 25 26 27
Solutions: 28 29
Theorems: 30 31 32 33 34 35 36 37
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References
Bibliography
 Diestel, Reinhard: "Graph Theory, 3rd Edition", Springer, 2005